Spokane police hunted down a man accused of killing a young mother 40 years ago by tricking him into mailing them an envelope.
That envelope contained the DNA that helped lead to his arrest.
David John Tibbett, now 74, is facing a second-degree murder charge in the death of 32-year-old Mary Ann Turner, whose body was found covered in dirt with her scarf and sweater wrapped around her neck near South Ivory Street and East Pacific Avenue in the early morning of Nov. 4, 1986.
Turner, who moved from Sacramento to Spokane, had a difficult life. She turned to prostitution to be able to eat, according to Spokesman-Review archives. Turner got pregnant at 13, gave up her child and got pregnant again at 15. That daughter eventually ran away, archives show. At the time of Turner's death, she was looking for her.
Tibbett made his first appearance in Spokane County court Thursday with scraggly white hair and a long white beard, clad in a yellow jumpsuit. He did not speak.
Spokane County Prosecutor Preston McCollam, sitting a seat away from Tibbett, read a brief statement to the judge on behalf of Turner's family. Her family appeared via Zoom and pleaded with the judge to keep Tibbett behind bars.
"Why would the court give him a chance to get out and disappear now that this has been brought to light?" McCollam read. "He has been free longer than Ms. Turner was alive."
Turner was seen multiple times the night of Nov. 4, according to court records. Her friend, Yolanda Snapp, told police at the time they had been "working the streets" together in the area of East First Avenue and South Magnolia. Turner got into a burnt-orange car around 2:45 a.m. The car drove westbound on East First Avenue.
The last time Turner was spotted was by two police officers. She was standing alone on the corner of Sprague Avenue and North Madelia Street, according to court records. Her body would be discovered around four hours later.
Spokane police investigators have looked into Turner's case for years. They sent out media releases pleading with the public for any help solving the case.
In one release, police asked for help identifying a bronze car that resembled a Ford Torino, according to court records. A "secret witness" called in with an anonymous tip and claimed the car was not a Ford Torino but a 1975 Ford Elite, copper brown with body damage. They also claimed Tibbett, known to "weird out with girls," was drunk in the area of the killing that night. Tibbett did own a 1976 bronze Ford Elite, but was never arrested, court records say.
The case sat cold for years.
In 2008, now-retired Spokane police Detective Kip Hollenbeck submitted DNA swabs from Turner's body and multiple cigarettes left at the scene to a forensic laboratory. They included swabs from under her fingernails, inside her mouth and on her body, according to court records. Scientists discovered the DNA left under her fingernails and the DNA left from an unknown male's semen had come from the same person.
It took another 16 years before the case would ramp up again. Othram, a forensic laboratory based in Texas, reported to Spokane police in 2025 they had successfully developed a suspect profile using familial genealogy databases.
A year later, the company reached out again — Othram scientists suggested police probe three brothers to determine if they were involved in Turner's death.
They named Darrel Robert Tibbett and Daniel Howard Tibbett, who both had died, and David John Tibbett. He was alive and still living in a house on East Decatur, the same house he lived in when Turner was killed in 1986.
Police knew Tibbett's car had been stolen and returned to him last year. They decided to come up with a ruse.
On Feb. 4 of this year, police records personnel sent Tibbett a letter in the mail asking him to confirm his car was no longer stolen. They asked him to sign the letter, with official police letterhead, and mail it back to the department.
It was an envelope you would have to lick to seal, court records say.
Police received Tibbett's letter eight days later. Spokane police Detective Zac Storment rushed the letter, without opening it, to the Washington State Patrol Crime Lab. Scientists concluded in March the DNA found under Turner's fingernails was 4.3 million times more likely to have matched the person who licked the envelope than anyone else in the United States.
Police descended on Tibbett's house Wednesday where they arrested him and searched his home, the department said in a news release.
Even before Turner's death, Tibbett was becoming dangerous, according to records. Spokane County Court archives show Tibbett was classified as a "sexual psychopath," a term in the '70s and '80s akin to today's sexually violent predator.
Washington law defines a sexually violent predator as someone who suffers from a personality disorder, has been convicted or charged with a sexually violent crime and is more likely to engage in sexual violence if not confined to a facility.
Tibbett was charged in 1970 with second-degree assault and rape, but later pleaded guilty to the assault charge. Court archives say he beat a woman with a pistol.
"He had been involved in attempted rapes," a psychologist wrote to county attorneys in 1971. "David was a longtime problem with the juvenile court for a variety of anti-social activities."
Tibbett was sent to Western State Hospital in 1971 and discharged after almost two years. In his discharge paperwork, hospital supervisors wrote he had made "sufficient progress" and should be considered for probation.
Tibbett was discharged on March 29, 1973, records show. He is currently being held in the Spokane County Jail on a $1 million bond.
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